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Help deciding on a buy [message #343861] Sun, 02 June 2019 20:02 Go to next message
jfkarls is currently offline  jfkarls   United States
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Location: Racine, Wisconsin
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Thanks for letting me in folks! Great site I spent most of the day reading your notes, suggestions ect,,,, GREAT stuff. OK here's where I could use your guys expertise: When I test drove it today I noticed a few things I could use your help with:
1) The most important was engine/exhaust fumes inside. The rubber seals looked to be good and well installed. Is this a common problem? and can it be rectified?
2) I had it floored and it slooooowwwllly got up to 55 - Is that normal? should it have more power? I did notice smoke when he was backing out
3) From reading here I understand that many of you have converted to headers - does that help with the fumes? warped cast iron manifolds that are 40 years old seems normal. My 67 Lincoln has the same issue
I'm not a complete neophyte; I was an airplane mechanic in the Army and I've rebuilt many jeeps cars ect but never anything like this cool rig. I'm really jazzed about potentially bringing one of these cool rigs back to life. So thanks in advance for any help you guys can give - Cheers JFK
Re: Help deciding on a buy [message #343862 is a reply to message #343861] Sun, 02 June 2019 20:44 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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exhaust fumes inside the cabin are never a good thing. Sounds like exhaust leaks between the exhaust manifolds and the heads. look, as much as possible, for obvious exhaust leak evidence around the manifolds.
since your question sounds like you do not own this one yet, the fastest fix may be to remove the exhaust manifolds, clean the surfaces, and re-install with remflex gaskets. search the forum for remflex and follow the install directions exactly.
of course, the coach may have a rusted out exhaust system. easy enough to replace.
headers on the GMC are used because the passenger side exhaust manifold for the 455 are not available as new old stock. they do not seem to add any additional power.
TOM


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] Help deciding on a buy [message #343865 is a reply to message #343862] Sun, 02 June 2019 22:30 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Location: Belmont, CA
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Tom,
You are correct that one does not gain much just by installing headers as
they are designed to work with 2.5Dia muffler with 3" mandrel bent pipes.
We find when we match these Low RPM Headers with the right combination
exhaust system, you will notice improved performance.
I know Miguel of MGM GMC and I are sold on the system.

On Sun, Jun 2, 2019 at 7:12 PM Thomas Phipps via Gmclist <
gmclist@list.gmcnet.org> wrote:

> exhaust fumes inside the cabin are never a good thing. Sounds like exhaust
> leaks between the exhaust manifolds and the heads. look, as much as
> possible, for obvious exhaust leak evidence around the manifolds.
> since your question sounds like you do not own this one yet, the fastest
> fix may be to remove the exhaust manifolds, clean the surfaces, and
> re-install with remflex gaskets. search the forum for remflex and follow
> the install directions exactly.
> of course, the coach may have a rusted out exhaust system. easy enough to
> replace.
> headers on the GMC are used because the passenger side exhaust manifold
> for the 455 are not available as new old stock. they do not seem to add any
> additional power.
> TOM
> --
> 2012 Phoenix Cruiser model 2552
> KA4CSG
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Help deciding on a buy [message #343870 is a reply to message #343865] Mon, 03 June 2019 07:38 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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Depends on your definition of slowly I imagine.
I find mine to be surprisingly quick for it's size.
I image it needs a tune up, but smoke is never good.


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: Help deciding on a buy [message #343871 is a reply to message #343861] Mon, 03 June 2019 08:03 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Location: Woodstock, IL
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The transmission is probably not kicking down as someone may have disconnected the electrical kick down or broken the switch on the gas pedal arm. Also if it's been sitting, and not fully warmed up the secondary air valve is most likely stuck or still engaged and not opening because the choke is not fully open. You will just be on the small carb primaries on the Qjet. Also most of these need a throttle cable adjustment to pull the throttle wide open. The secondaries don't open until the last 1/3 or so of pedal travel so cable must be set correctly.
If you dont' hear an exhaust leak up front, you don't have one. It you have one you will hear it. A drop or 2 of fuel or oil burning off will make you think you have major fumes. If it's been sitting this may be the case. If it has been sitting and smoke is blue, owner may have fogged engine (not likely) or a couple drops of oil have slid down the valve guides and are burning off. If engine has no ticks or knocks, it's usually good engine. See if smoke goes away after a drive circuit. If smoke is white it's coolant and there are bigger issues.


John Lebetski
Woodstock, IL
77 Eleganza II
Re: Help deciding on a buy [message #343877 is a reply to message #343861] Mon, 03 June 2019 11:00 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Location: St. Cloud, MN
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stink is not normal..... but these are old and exhaust systems leak, and oil leaks if not addressed. All repairable. But oil smell or exhaust smell is a completely unrelated to weather you run headers or Manifolds.


without towing, it should accelerate decent enough. it should also climb and drive 60-70MPH easy enough. sounds like there are some issues.


headers are a good route to go, but I know a few that stick with Manifolds. I know a couple that have gotten what seem to be new manifolds from cinnabar, and are plenty happy. Main thing is to make sure you use good gaskets(copper preferred if surfaces are in great shape. you can get by with RemFlex gaskets if surfaces are not 100%.) and both the head and the manifold are in good shape. if the manifold is bad, or if it was run a long time with leaks, you may have a head surface problem.







Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/

[Updated on: Mon, 03 June 2019 11:04]

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Re: Help deciding on a buy [message #343904 is a reply to message #343877] Tue, 04 June 2019 09:35 Go to previous messageGo to next message
jfkarls is currently offline  jfkarls   United States
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THANKS GUYS!!!! This site is absolutely outstanding - ok this all confirms a good feeling about buying this unit - thanks again guy, so glad I found this site

JFK
Re: Help deciding on a buy [message #343925 is a reply to message #343904] Tue, 04 June 2019 17:09 Go to previous messageGo to next message
jfkarls is currently offline  jfkarls   United States
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thanks guys - bought it - pic it up Saturday Smile

Joe & Valerie Karls 1976 Eleganza II, & 1976 Palm Beach - Also own 1967 Lincoln Continental Convertible,
Re: Help deciding on a buy [message #343938 is a reply to message #343925] Wed, 05 June 2019 08:50 Go to previous messageGo to next message
Justin Brady is currently offline  Justin Brady   United States
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Congrats!
When I bought mine it didn't want to shift out of 2nd and took forever to get up to speed etc.
A few hours and some advice from here and I was up and running as intended.
Now I can cruise at 80 all day if I want to and get there quickly(-ish).


Justin Brady http://www.thegmcrv.com/ 1976 Palm Beach 455
Re: Help deciding on a buy [message #343943 is a reply to message #343938] Wed, 05 June 2019 11:32 Go to previous message
jfkarls is currently offline  jfkarls   United States
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yah this is a great site - a lot of great folks. I've rehabbed a number of vehicles and each had their forums/sites but this one is by fare the best for knowledge help and community!!!

Joe & Valerie Karls 1976 Eleganza II, & 1976 Palm Beach - Also own 1967 Lincoln Continental Convertible,
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